Dry soil along railroads in Kalamazoo Co.; the only other Michigan collection, and the first for the state, is from the banks of the Saginaw River in Bay Co. (R. R. Dreisbach 6972 in 1930, MICH). Introduced from farther west.

The awn tends to be slender, deciduous, and conspicuously curly in this species, while in H. spartea, it is stouter, persistent, and merely bent once or twice above the twisted base. The base of the panicle is generally enclosed in the inflated upper sheath in H. comata, while in H. spartea it is usually exserted.